Fig. 5
aB0 field homogeneity at 2 years post manufacture across the nine phantom compartments as a measure of off-resonance in hertz at 1.5 T (blue, averaged for three phantoms) and 3 T (green, averaged for another three phantoms). These are extremely small shifts in frequency (e.g., 10 Hz = 0.08 ppm at 3 T) and should not be regarded as significantly different between the tube compartments. b Diagonal profiles of the B1 field at 2 years post manufacture as per red discontinuous lines (right panels) in six phantoms: three at 1.5 T scanned on 1.5 T MAGNETOM Avanto (Siemens Healthineers; software syngo MR B17A); example field map (c) and three at 3 T scanned on 3 T MAGNETOM Skyra (Siemens Healthineers; software syngo MR D13C); example field map (d)